FIONX vs. FSOSX

Last updated Apr 1, 2026

Compare and contrast key facts about Fidelity SAI International Index Fund (FIONX) and Fidelity Series Overseas Fund (FSOSX).

FIONX is managed by Fidelity. It was launched on Jan 5, 2016. FSOSX is managed by Fidelity. It was launched on Jun 21, 2019.

Performance

FIONX vs. FSOSX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity SAI International Index Fund (FIONX) and Fidelity Series Overseas Fund (FSOSX). The values are adjusted to include any dividend payments, if applicable.

FIONX vs. FSOSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
FIONX Fidelity SAI International Index Fund	-1.95%	31.85%	3.64%	18.22%	-14.19%	11.24%	8.17%	6.99%
FSOSX Fidelity Series Overseas Fund	-5.69%	21.29%	5.87%	21.49%	-23.25%	19.59%	16.36%	7.78%

Returns By Period

In the year-to-date period, FIONX achieves a -1.95% return, which is significantly higher than FSOSX's -5.69% return.

FIONX

• 1D: 0.41%
• 1M: -10.88%
• YTD: -1.95%
• 6M: 2.53%
• 1Y: 19.82%
• 3Y*: 13.41%
• 5Y*: 7.89%
• 10Y*: —

FSOSX

• 1D: 0.36%
• 1M: -11.39%
• YTD: -5.69%
• 6M: -5.28%
• 1Y: 7.28%
• 3Y*: 10.01%
• 5Y*: 5.83%
• 10Y*: —

*Multi-year figures are annualized to reflect compound growth (CAGR)

FIONX vs. FSOSX - Expense Ratio Comparison

FIONX has a 0.04% expense ratio, which is higher than FSOSX's 0.01% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

FIONX

Fidelity SAI International Index Fund

FSOSX

Fidelity Series Overseas Fund

Return for Risk

FIONX vs. FSOSX — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

FIONX

FIONX Risk / Return Rank: 62
FIONX Sharpe Ratio Rank: 63
FIONX Sortino Ratio Rank: 61
FIONX Omega Ratio Rank: 59
FIONX Calmar Ratio Rank: 65
FIONX Martin Ratio Rank: 61

FSOSX

FSOSX Risk / Return Rank: 14
FSOSX Sharpe Ratio Rank: 14
FSOSX Sortino Ratio Rank: 13
FSOSX Omega Ratio Rank: 13
FSOSX Calmar Ratio Rank: 15
FSOSX Martin Ratio Rank: 16

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

FIONX vs. FSOSX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity SAI International Index Fund (FIONX) and Fidelity Series Overseas Fund (FSOSX). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

	FIONX	FSOSX	Difference
Sharpe ratio Return per unit of total volatility	1.11	0.34	+0.78
Sortino ratio Return per unit of downside risk	1.55	0.58	+0.97
Omega ratio Gain probability vs. loss probability	1.23	1.08	+0.15
Calmar ratio Return relative to maximum drawdown	1.49	0.40	+1.09
Martin ratio Return relative to average drawdown	5.86	1.51	+4.34
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

FIONX vs. FSOSX - Sharpe Ratio Comparison

The current FIONX Sharpe Ratio is 1.11, which is higher than the FSOSX Sharpe Ratio of 0.34. The chart below compares the historical Sharpe Ratios of FIONX and FSOSX, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	FIONX	FSOSX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.11	0.34	+0.78
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.50	0.34	+0.16
Sharpe Ratio (All Time) Calculated using the full available price history	0.51	0.43	+0.08

Correlation

The correlation between FIONX and FSOSX is 0.94, which is considered to be high. That indicates a strong positive relationship between their price movements. Having highly-correlated positions in a portfolio may signal a lack of diversification, potentially leading to increased risk during market downturns.

Dividends

FIONX vs. FSOSX - Dividend Comparison

FIONX's dividend yield for the trailing twelve months is around 3.34%, less than FSOSX's 9.70% yield.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017
FIONX Fidelity SAI International Index Fund	3.34%	3.28%	3.06%	2.18%	3.34%	2.65%	1.91%	3.16%	3.00%	0.52%
FSOSX Fidelity Series Overseas Fund	9.70%	9.15%	2.25%	1.63%	1.80%	2.92%	1.12%	0.37%	0.00%	0.00%

Drawdowns

FIONX vs. FSOSX - Drawdown Comparison

The maximum FIONX drawdown since its inception was -33.69%, roughly equal to the maximum FSOSX drawdown of -35.36%. Use the drawdown chart below to compare losses from any high point for FIONX and FSOSX.

Drawdown Indicators

	FIONX	FSOSX	Difference
Max Drawdown Largest peak-to-trough decline	-33.69%	-35.36%	+1.67%
Max Drawdown (1Y) Largest decline over 1 year	-11.40%	-12.39%	+0.99%
Max Drawdown (5Y) Largest decline over 5 years	-29.49%	-35.36%	+5.87%
Current Drawdown Current decline from peak	-10.88%	-11.89%	+1.01%
Average Drawdown Average peak-to-trough decline	-6.44%	-7.90%	+1.46%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.04%	3.31%	-0.27%

Volatility

FIONX vs. FSOSX - Volatility Comparison

The current volatility for Fidelity SAI International Index Fund (FIONX) is 7.05%, while Fidelity Series Overseas Fund (FSOSX) has a volatility of 8.28%. This indicates that FIONX experiences smaller price fluctuations and is considered to be less risky than FSOSX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FIONX	FSOSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	7.05%	8.28%	-1.23%
Volatility (6M) Calculated over the trailing 6-month period	10.64%	11.94%	-1.30%
Volatility (1Y) Calculated over the trailing 1-year period	16.83%	18.25%	-1.42%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	15.83%	17.35%	-1.52%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	16.49%	18.93%	-2.44%